Blower fan and air conditioner having the same

ABSTRACT

A blower fan may include a hub fixed to a rotary shaft, a main rib disposed to surround the hub while being spaced apart from an outer circumference of the hub, a plurality of auxiliary ribs to connect the hub to the main rib, and a plurality of blades connected to an outer circumference of the main rib so as to generate an air stream during rotation of the blower fan. The plurality of auxiliary ribs may be provided around the hub so as to generate an air stream during the rotation of the blower fan in a same direction with the plurality of blades.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Korean PatentApplication No. 2014-0059947, filed May 19, 2014, the subject matter ofwhich is incorporated herein by reference.

BACKGROUND

1. Field

Embodiments may relate to a blower fan and an air conditioner having thesame.

2. Background

An air conditioner is an apparatus that cools or heats a room using arefrigeration cycle including a compressor, an outdoor heat exchanger,an expansion valve, and an indoor heat exchanger. That is, the airconditioner may be configured as a cooler that cools a room or as aheater that heats a room. The air conditioner may be configured as aheater and cooler that cools and heats a room.

The air conditioner may be classified as a window type air conditioneror a separate type (or split type) air conditioner. The window type airconditioner and the separate type air conditioner are identical infunction to each other except that the window type air conditioner,having an integrated cooling and heat dissipation function, is directlyinstalled in an opening formed through the wall of a house or in awindow of the house, whereas the separate type air conditioner includesan indoor unit, including an indoor heat exchanger, installed indoors,an outdoor unit, including a compressor and an outdoor heat exchanger,installed outdoors, and a refrigerant pipe connected between the indoorunit and the outdoor unit.

The outdoor heat exchanger of the outdoor unit or the indoor unitperforms heat exchange between outdoor air and a refrigerant. Theoutdoor unit or the indoor unit includes a blower fan to blow theoutdoor air for smooth heat exchange between the outdoor air and therefrigerant.

A blower fan may be configured to have a structure in which a main plateof the blower fan extends along the outer circumference of a hub suchthat the main plate protrudes outward perpendicularly from a rotaryshaft of the blower fan to surround the outer circumference of the hub.

When blades are rotated, an air stream is generated from a front F to arear R of the blower fan in an axial direction of the blower fan by theblades.

At this time, a space defined between the main plate and the hub isclosed such that the air stream cannot pass through the space. As aresult, the air stream generated by rotation of the blades forms an eddyon the main plate at the rear R in an axial direction of the blower fan.

BRIEF DESCRIPTION OF THE DRAWINGS

Arrangements and embodiments may be described in detail with referenceto the following drawings in which like reference numerals refer to likeelements and wherein:

FIG. 1 is a view schematically showing construction of an airconditioner according to an embodiment;

FIG. 2 is a view showing an outdoor unit of an air conditioner accordingto an embodiment;

FIG. 3 is an exploded perspective view showing the outdoor unit of theair conditioner shown in FIG. 2;

FIG. 4 is a perspective view showing a blower apparatus according to anembodiment;

FIG. 5 is a sectional view showing the blower apparatus according to theembodiment;

FIG. 6 is a perspective view showing a blower fan according to anembodiment;

FIG. 7 is a plan view of the blower fan shown in FIG. 6;

FIG. 8 is a side view of the blower fan shown in FIG. 6;

FIG. 9A is a view illustrating the flow of air generated by a blowerfan;

FIG. 9B is view illustrating the flow of air generated by the blower fanaccording to the embodiment; and

FIG. 10 is a plan view showing a blower fan according to anotherembodiment.

DETAILED DESCRIPTION

Advantages and features of embodiments and a method of achieving thesame will be more clearly understood from embodiments described belowwith reference to the accompanying drawings. However, embodiments arenot limited to the following embodiments but may be implemented invarious different forms. Embodiments are provided merely to completedisclosure and to fully provide a person having ordinary skill in theart to which the embodiments pertain with the category. Whereverpossible, the same reference numbers will be used throughout thespecification to refer to the same or like elements.

Reference may now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings.

FIG. 1 is a view schematically showing construction of an airconditioner according to an embodiment. Other embodiments andconfigurations may also be provided.

Referring to FIG. 1, the air conditioner 1 may include a compressor 20to compress a refrigerant, an outdoor heat exchanger 170 installedoutdoors to perform heat exchange between the refrigerant and outdoorair, an indoor heat exchanger 50 installed indoors to perform heatexchange between the refrigerant and indoor air, a switching valve 80 toguide the refrigerant discharged from the compressor 20 to the outdoorheat exchanger 170 during a cooling operation and to guide therefrigerant discharged from the compressor 20 to the indoor heatexchanger 50 during a heating operation.

The air conditioner 1 includes an outdoor unit disposed outdoors and anindoor unit disposed indoors. The outdoor unit and the indoor unit areconnected to each other. The outdoor unit includes the compressor 20,the outdoor heat exchanger 170, an outdoor expansion valve 70, and a gasand liquid separator 27. The indoor unit includes the indoor heatexchanger 50 and an indoor expansion valve 60.

The compressor 20 is installed in the outdoor unit to compress alow-temperature, low-pressure refrigerant, introduced into thecompressor 20, into a high-temperature, high-pressure refrigerant. Thecompressor 20 may be configured to have various structures. For example,the compressor 20 may be a reciprocation type compressor 20 using acylinder and a piston, a scroll type compressor 20 using a rotatablescroll and a stationary scroll, or an inverter type compressor 20 toadjust a compression rate of the refrigerant based on a real indoortemperature, a real outdoor temperature, and a total number of indoorunits under operation when a desired indoor temperature is set. One ormore compressors 20 may be provided. In this embodiment, two compressors20 are provided.

The compressor 20 is connected to the switching valve 80 and the gas andliquid separator 27. The compressor 20 includes an inlet port 21,through which a refrigerant evaporated by the indoor heat exchanger 50is introduced into the compressor 20 during the cooling operation or arefrigerant evaporated by the outdoor heat exchanger 170 is introducedinto the compressor 20 during the heating operation, and an outlet port23, through which a compressed refrigerant is discharged from thecompressor 20.

The compressor 20 compresses the refrigerant introduced through theinlet port 21 in a compression compartment. The compressor 20 dischargesthe compressed refrigerant through the outlet port 23. The refrigerantdischarged through the outlet port 23 flows to the switching valve 80.

The switching valve 80 is a flow channel switching valve for switchingbetween cooling and heating. The switching valve 80 guides therefrigerant compressed by the compressor 20 to the outdoor heatexchanger 170 during the cooling operation and guides the refrigerantcompressed by the compressor 20 to the indoor heat exchanger 50 duringthe heating operation. That is, the switching valve 80 functions toguide the refrigerant compressed by the compressor 20 to a condenser.

The switching valve 80 is connected to the outlet port 23 of thecompressor 20 and the gas and liquid separator 27. Additionally, theswitching valve 80 is connected to the indoor heat exchanger 50 and theoutdoor heat exchanger 170. During the cooling operation, the switchingvalve 80 connects the outlet port 23 of the compressor 20 to the outdoorheat exchanger 170 and connects the indoor heat exchanger 50 to the gasand liquid separator 27. In another embodiment, however, the switchingvalve 80 may connect the indoor heat exchanger 50 to the inlet port 21of the compressor 20 during the cooling operation.

During the heating operation, the switching valve 80 connects the outletport 23 of the compressor 20 to the indoor heat exchanger 50 andconnects the outdoor heat exchanger 170 to the gas and liquid separator27. In another embodiment, however, the switching valve 80 may connectthe outdoor heat exchanger 170 to the inlet port 21 of the compressor 20during the heating operation.

The switching valve 80 may be embodied by various modules that arecapable of connecting different flow channels to each other. In thisembodiment, the switching valve 80 is a four-way valve. In anotherembodiment, however, the switching valve 80 may be embodied by variousvalves and combinations thereof, such as a combination of two three-wayvalves.

The outdoor heat exchanger 170 is disposed at the outdoor unit installedoutdoors to perform heat exchange between the refrigerant passingthrough the outdoor heat exchanger 170 and outdoor air. During thecooling operation, the outdoor heat exchanger 170 functions as acondenser to condense the refrigerant. On the other hand, during theheating operation, the outdoor heat exchanger 170 functions as anevaporator to evaporate the refrigerant.

The outdoor heat exchanger 170 is connected to the switching valve 80and the outdoor expansion valve 70. During the cooling operation, therefrigerant compressed by the compressor 20 passes through the outletport 23 of the compressor 20 and the switching valve 80 and is thenintroduced into the outdoor heat exchanger 170, in which the refrigerantis condensed. The condensed refrigerant flows to the outdoor expansionvalve 70. On the other hand, during the heating operation, therefrigerant expanded by the outdoor expansion valve 70 flows to theoutdoor heat exchanger 170, in which the refrigerant is evaporated. Theevaporated refrigerant flows to the switching valve 80.

During the cooling operation, the outdoor expansion valve 70 is fullyopened to allow the refrigerant to pass therethrough. On the other hand,during the heating operation, an opening degree of the outdoor expansionvalve 70 is adjusted to expand the refrigerant. The outdoor expansionvalve 70 is disposed between the outdoor heat exchanger 170 and aninjection module 90.

During the cooling operation, the outdoor expansion valve 70 allows therefrigerant introduced from the outdoor heat exchanger 170 to passtherethrough such that the refrigerant is guided to the injection module90. On the other hand, during the heating operation, the outdoorexpansion valve 70 may expand the refrigerant through heat exchange inthe injection module 90 and guide the expanded refrigerant to theoutdoor heat exchanger 170.

The indoor heat exchanger 50 is disposed in the indoor unit installedindoors to perform heat exchange between the refrigerant passing throughthe indoor heat exchanger 50 and indoor air. During the coolingoperation, the indoor heat exchanger 50 functions as an evaporator toevaporate the refrigerant. On the other hand, during the heatingoperation, the indoor heat exchanger 50 functions as a condenser tocondense the refrigerant.

The indoor heat exchanger 50 is connected to the switching valve 80 andthe indoor expansion valve 60. During the cooling operation, therefrigerant expanded by the indoor expansion valve 60 flows to theindoor heat exchanger 50, in which the refrigerant is evaporated. Theevaporated refrigerant flows to the switching valve 80. On the otherhand, during the heating operation, the refrigerant compressed by thecompressor 20 passes through the outlet port 23 of the compressor 20 andthe switching valve 80 and is then introduced into the indoor heatexchanger 50, in which the refrigerant is condensed. The condensedrefrigerant flows to the indoor expansion valve 60.

During the cooling operation, an opening degree of the indoor expansionvalve 60 is adjusted to expand the refrigerant. On the other hand,during the heating operation, the indoor expansion valve 60 is fullyopened to allow the refrigerant to pass therethrough. The indoorexpansion valve 60 is disposed between the indoor heat exchanger 50 andthe injection module 90.

During the cooling operation, the indoor expansion valve 60 expands therefrigerant flowing to the indoor heat exchanger 50. On the other hand,during the heating operation, the indoor expansion valve 60 allows therefrigerant introduced from the indoor heat exchanger 50 to passtherethrough such that the refrigerant is guided to the injection module90.

The injection module 90 is disposed between the outdoor heat exchanger170 and the indoor heat exchanger 50 to inject a portion of therefrigerant flowing between the outdoor heat exchanger 170 and theindoor heat exchanger 50 to the compressor 20. That is, the injectionmodule 90 may inject a portion of the refrigerant flowing from thecondenser to the expansion valve to the compressor 20. The injectionmodule 90 is connected to the outdoor expansion valve 70 and the indoorexpansion valve 60.

The injection module 90 includes an injection expansion valve 91 toexpand a portion of the refrigerant flowing between the outdoor heatexchanger 170 and the indoor heat exchanger 50 and an injection heatexchanger 92 to perform heat exchange between another portion of therefrigerant flowing between the indoor heat exchanger 50 and the outdoorheat exchanger 170 and the refrigerant expanded by the injectionexpansion valve 91. The injection heat exchanger 92 guides theheat-exchanged and thus evaporated refrigerant to an injection port 22of the compressor 20. In another embodiment, however, the injectionmodule 90 may not be included in the air conditioner 1.

The gas and liquid separator 27 may be disposed between the switchingvalve 80 and the inlet port 21 of the compressor 20. The gas and liquidseparator 27 is connected to the switching valve 80 and the inlet port21 of the compressor 20. The gas and liquid separator 27 separates therefrigerant evaporated by the indoor heat exchanger 50 during thecooling operation or the refrigerant evaporated by the outdoor heatexchanger 170 during the heating operation into a gas refrigerant and aliquid refrigerant and guides the gas refrigerant to the inlet port 21of the compressor 20. That is, the gas and liquid separator 27 separatesthe refrigerant evaporated by the evaporator into a gas refrigerant anda liquid refrigerant and guides the gas refrigerant to the inlet port 21of the compressor 20.

The refrigerant evaporated by the outdoor heat exchanger 170 or theindoor heat exchanger 50 is introduced into the gas and liquid separator27 through the switching valve 80. Consequently, the gas and liquidseparator 27 may be maintained at a temperature of about 0 to 5° C. andcold energy may be dissipated from the gas and liquid separator 27. Thesurface temperature of the gas and liquid separator 27 is lower than thetemperature of the refrigerant condensed by the outdoor heat exchanger170 during the cooling operation. The gas and liquid separator 27 may beformed in a cylindrical shape extending in a longitudinal direction.

FIG. 2 is a view showing an outdoor unit of an air conditioner accordingto an embodiment. FIG. 3 is an exploded perspective view showing theoutdoor unit of the air conditioner shown in FIG. 2. Other embodimentsand configurations may also be provided.

Referring to FIGS. 2 and 3, the outdoor unit of the air conditioner 1includes an outdoor unit base 110 defining the bottom thereof, anoutdoor unit body 100 coupled to the outdoor unit base 110, the outdoorunit body 100 being provided at the lateral side thereof with suctionholes, through which air is suctioned, the outdoor unit body 100 beingprovided at the top thereof with a discharge hole 143, an outdoor heatexchanger 170 disposed in the outdoor unit body 100 such that theoutdoor heat exchanger 170 corresponds to the suction holes, a blowerapparatus 200 provided in the discharge hole 143 of the outdoor unitbody 100 to blow air in a vertical direction, and an suction apparatusprovided at the lower part of the outdoor unit body 100 to suction airin a horizontal direction.

In this embodiment, a blower fan 300 is described as being located inthe outdoor unit. On the other hand, the blower fan 300 may be locatedin the indoor unit. That is, the blower fan 300 may be located adjacentto the heat exchanger provided in the air conditioner.

In this embodiment, an upward and downward direction means a verticaldirection, which is a direction of gravity, and a forward and backwarddirection and a left and right direction mean a horizontal directionperpendicular to the upward and downward direction.

An outdoor unit case, which is constituted by the outdoor unit base 110and the outdoor unit body 100, defines an external appearance of theoutdoor unit of the air conditioner 1. The outdoor unit base 110 definesthe external appearance of the bottom of the outdoor unit case. Acompressor 20, oil separators 28 and 29, a gas and liquid separator 27,and an outdoor heat exchanger 170 are installed at the top of theoutdoor unit base 110.

The outdoor unit body 100 is coupled to the outdoor unit base 110. Theoutdoor unit body 100 is formed in the shape of a rectangularparallelepiped opened at the bottom thereof. The suction holes, throughwhich air is suctioned, are formed at the lateral side of the outdoorunit body 100.

The discharge hole 143 is formed at an upper region of the outdoor unitcase. More specifically, the discharge hole 143 is formed at the top ofthe outdoor unit body 100.

The suction holes may be formed at three side parts of the lateral sideof the outdoor unit body 100. More specifically, the suction holes maybe formed at the rear, the left side, and the right side of the outdoorunit body 100.

In this embodiment, the suction holes include left side suction holes123, right side suction holes 133, and rear suction holes 163.

The outdoor unit body 100 includes a left side panel 120 defining theleft side thereof, a right side panel 130 defining the right sidethereof, a top panel 140 defining the top thereof, a front panel 150defining the front thereof, and a rear panel 160 defining the rearthereof.

The left side panel 120 defines the external appearance of the left sideof the outdoor unit. The left side panel 120 is coupled to the left sideof the outdoor unit base 110. The left side panel 120 is provided with aleft side grill 122, through which outdoor air is suctioned into theoutdoor unit body 100. The left side grill 122 defines the left sidesuction holes 123, through which outdoor air is suctioned from the leftside.

The right side panel 130 defines the external appearance of the rightside of the outdoor unit. The right side panel 130 is coupled to theright side of the outdoor unit base 110. The right side panel 130 isprovided with a right side grill 132, through which outdoor air issuctioned into the outdoor unit body 100. The right side grill 132defines the right side suction holes 133, through which outdoor air issuctioned from the right side.

The top panel 140 defines the external appearance of the top of theoutdoor unit. The top panel 140 is coupled to the upper end of the leftside panel 120 and the upper end of the right side panel 130. Thedischarge hole 143 is formed at the top panel 140. The top panel 140 maybe provided with a discharge grill 142, which is located above thedischarge hole 143.

The front panel 150 defines the external appearance of the front of theoutdoor unit. The front panel 150 is disposed at the front of a spacedefined by the outdoor unit base 110, the left side panel 120, the rightside panel 130, and the top panel 140.

The rear panel 160 defines the external appearance of the rear of theoutdoor unit. The rear panel 160 is disposed at the rear of the spacedefined by the outdoor unit base 110, the left side panel 120, the rightside panel 130, and the top panel 140.

The rear panel 160 is provided with a rear grill 162, through whichoutdoor air is suctioned into the outdoor unit body 100. The rear grill162 defines the rear suction holes 163, through which outdoor air issuctioned from the rear.

The outdoor heat exchanger 170 is disposed in the outdoor unit body 100such that the outdoor heat exchanger 170 corresponds to the suctionholes. In this embodiment, the suction holes include left side suctionholes 123, the right side suction holes 133, and the rear suction holes163. To this end, the outdoor heat exchanger 170 is formed in the shapeof in horizontal section such that the outdoor heat exchanger 170 hasthree sides.

The outdoor heat exchanger 170 having three sides is disposed so as tosurround the compressor 20, the oil separators 28 and 29, and the gasand liquid separator 27 installed at the top of the outdoor unit base110.

The left side of the outdoor heat exchanger 170 is disposed so as tocorrespond to the left side suction holes 123 formed at the left sidegrill 122, the right side of the outdoor heat exchanger 170 is disposedso as to correspond to the right side suction holes 133 formed at theright side grill 132, and the rear of the outdoor heat exchanger 170,which is located between the left side and the right side of the outdoorheat exchanger 170, is disposed so as to correspond to the rear suctionholes 163 formed at the rear grill 162.

The blower apparatus 200 may include a blower fan 300 rotated by a motor230 and an orifice 210, surrounding the blower fan 300, to guide airblown by the blower fan 300.

The blower fan 300 is disposed under the top panel 140 such that theblower fan 300 corresponds to the discharge hole 143.

The blower fan 300 is supported by a discharge bracket connected to thefront panel 150 and the rear panel 160. The blower fan 300 is rotated bythe motor 230. The motor 230 is installed at the discharge bracket.

The blower fan 300 is rotated to generate a pressure difference betweenthe front and the rear of the blower fan 300 such that air flows in onedirection. The blower fan 300 may hereinafter be described in detail.

The suction apparatus is provided at the lower part of the outdoor unitbody 100 to suction air in a horizontal direction. The suction apparatusis disposed above the outdoor unit base 110. The suction apparatusincludes a suction motor 196 and a suction fan 198 rotated by thesuction motor 196. The suction fan 198 is supported by a suction bracket197 connected to the top of the outdoor unit base 110. The suction fan198 is rotated by the suction motor 196. The suction motor 196 isinstalled at the suction bracket 197.

The suction fan 198 circulates outdoor air together with the blowerapparatus 200 such that the outdoor heat exchanger 170 performs heatexchange between the outdoor air and the refrigerant.

In a case in which the blower apparatus 200 and the suction fan 198circulate outdoor air in cooperation with each other such that theoutdoor heat exchanger 170 performs heat exchange between the outdoorair and the refrigerant, efficiency of the air conditioner 1 during acooling/heating operation is higher than in a case in which only theblower apparatus 200 circulates the outdoor air without the suction fan198 such that the outdoor heat exchanger 170 performs heat exchangebetween the outdoor air and the refrigerant.

The suction fan 198 may be an axial fan, having a horizontal shaft, tosuction outdoor air into the outdoor unit body 100. The shaft of thesuction fan 198 extends in a forward and backward direction to suctionair in the forward and backward direction.

A controller 180 controls the compressor 20, the outdoor expansion valve70, the indoor expansion valve 60, the switching valve 80, the suctionmotor 196, and the motor 230 based on required cooling and heatingperformance.

FIG. 4 is a perspective view showing a blower apparatus according to anembodiment. FIG. 5 is a sectional view showing the blower apparatusaccording to the embodiment. Other embodiments and configurations mayalso be provided.

Referring to FIGS. 4 and 5, the blower apparatus 200 according to theembodiment includes a blower fan 300 rotated about a shaft thereof toblow air heat-exchanged with the refrigerant by the outdoor heatexchanger 170 in one direction and an orifice 210 installed in the casesuch that the inside and the outside of the case communicate with eachother through the orifice 210 to guide the air blown by the blower fan300. The orifice 210 includes a discharge part 211 to guide airdischarged from the front F to the rear R of the blower apparatus 200 inan axial direction of the blower apparatus 200 by the blower fan 300.The sectional area of the discharge part 211 is gradually increased fromthe front F to the rear R of the blower apparatus 200 in the axialdirection of the blower apparatus 200.

The blower fan 300 is disposed under the discharge hole 143 of theoutdoor unit body in an upward and downward direction to blow air in theupward and downward direction (from the front F to the rear R of theblower apparatus 200 in the axial direction of the blower apparatus200).

That is, the blower fan 300 discharges outdoor air from the outdoor unitbody.

The blower fan 300 blows outdoor air such that the outdoor heatexchanger 170 performs heat exchange between the outdoor air and therefrigerant.

The blower fan 300 discharges outdoor air suctioned through the suctionholes outward from the case. The blower fan 300 may hereinafter bedescribed in detail.

The front F of the blower apparatus 200 in the axial direction of theblower apparatus 200 may be aligned with a direction of gravity (adownward direction).

The orifice 210 is installed in the case such that the inside and theoutside of the case communicate with each other through the orifice 210to guide the air blown by the blower fan 300.

More specifically, the orifice 210 may be located at the upper region ofthe case such that the orifice 210 communicates with the discharge hole143.

The blower fan 300 is disposed inside the orifice 210.

More specifically, the orifice 210 may form a closed space to surroundthe blower fan 300 on a horizontal plane perpendicular to the axialdirection of the blower apparatus 200. The axis means a shaft aboutwhich the blower fan 300 is rotated.

The internal space of the orifice 210 may be formed in a shape in whichthe front F and the rear R of the blower apparatus 200 in the axialdirection of the blower apparatus 200 are opened and the orifice 210surrounds the blower fan 300 in a direction perpendicular to the axialdirection of the blower apparatus 200. That is, the orifice 210 isformed approximately in a cylindrical shape.

The internal space of the orifice 210 defines a flow channel to guideair blown by the blower fan 300. An inlet port 212, through which air isintroduced by the blower fan 300, is formed in an internal space of theorifice 210 at the front F of the blower apparatus 200 in the axialdirection of the blower apparatus 200 and an outlet port 214, throughwhich air is discharged by the blower fan 300, is formed in the internalspace of the orifice 210 at the rear R of the blower apparatus 200 inthe axial direction of the blower apparatus 200.

The orifice 210 may be installed in the case. More specifically, theorifice 210 is disposed under the top panel in a state in which theorifice 210 is connected to the front panel and the rear panel.

For example, the orifice 210 may include a discharge part 211, aconnection part 215, and a suction part 213.

The discharge part 211 guides air discharged from the front F to therear R of the blower apparatus 200 in the axial direction of the blowerapparatus 200 by the blower fan 300.

The discharge part 211 defines the outlet port 214. More specifically,the discharge part 211 may have a shape having the outlet port 214defined therein. For example, the discharge part 211 may be formed in ashape in which the front F and the rear R of the blower apparatus 200 inthe axial direction of the blower apparatus 200 are opened and thedischarge part 211 surrounds the blower fan 300 in a directionperpendicular to the axial direction of the blower apparatus 200. Thatis, the discharge part 211 is formed approximately in a cylindricalshape.

The discharge part 211 is located at the rear R of the blower fan 300 inthe axial direction of the blower apparatus 200.

The center of the discharge part 211 may be aligned with the shaft ofthe blower fan 300.

The sectional area of the discharge part 211 is gradually increased fromthe front F to the rear R of the blower apparatus 200 in the axialdirection of the blower apparatus 200. Additionally, the width of thedischarge part 211 is also gradually increased.

Consequently, noise of air discharged by the blower fan 300 isproportional to flow speed of air. The flow speed of the air is a valueobtained by dividing the flow rate of air by a sectional areaperpendicular to a flow direction of the air.

According to law of mass conservation, the flow rate of air is uniformlymaintained irrespective of position in a flow direction (axialdirection) of the air. When the sectional area of the discharge part 211is gradually increased, therefore, the flow speed of the air becomesslow. As a result, noise of the discharged air is reduced.

When the flow speed of the air is decreased, a difference in flow speedbetween the discharged air and external air at a rear end 211A of thedischarge part 211 is reduced with the result that generation of an eddyin the air is restrained. As generation of an eddy in the air isrestrained, efficiency of the outdoor unit is improved.

The sectional area means the area of a plane perpendicular to the axialdirection.

More specifically, the front end of the discharge part 211 is connectedto the connection part 215 and the rear end 211A of the discharge part211 is located more adjacent to the rear R in the axial direction thanthe rear end of the blower fan 300. Consequently, it is possible tosufficiently reduce the flow speed of the air having passed through theblower fan 300.

The front end of the discharge part 211 means an end of the dischargepart 211 located at the front F in the axial direction and the rear end211A of the discharge part 211 means an end of the discharge part 211located at the rear R in the axial direction.

That is, the discharge part 211 may have a uniform height. The height ofthe discharge part 211 means the distance from the front end of thedischarge part 211 to the rear end 211A of the discharge part 211.

The axial section of the discharge part 211 may have a linear or curvedshape. The axial section means the sectional area of a plane parallel tothe axial direction.

A ratio of a width L2 of the rear end 211A of the discharge part 211 toa width L1 of the connection part 215 may be 1.6:1 to 1.4:1. If thewidth L2 of the rear end 211A of the discharge part 211 is greater than1.6 times the width L1 of the connection part 215, the sectional area ofthe discharge part 211 is sharply increased with the result that it isnot possible to guide air flowing into the discharge port 211. On theother hand, if the width L2 of the rear end 211A of the discharge part211 is less than 1.4 times the width L1 of the connection part 215, thesectional area of the discharge part 211 is gently increased with theresult that it is not possible to reduce the flow speed of the airdischarged from the discharge part 211.

In a case in which the sectional shape of the discharge part 211 iscircular, the width L2 of the rear end 211A of the discharge part 211means the diameter of an internal space of the discharge part 211. Onthe other hand, in a case in which the sectional shape of the dischargepart 211 is polygonal, the width L2 of the rear end 211A of thedischarge part 211 means the average width of the internal space of thedischarge part 211. Additionally, in a case in which the sectional shapeof the connection part 215 is circular, the width L1 of the connectionpart 215 means the diameter of an internal space of the connection part215.

Additionally, a difference between the width L2 of the rear end 211A ofthe discharge part 211 and the width L1 of the connection part 215 maybe 50% to 100% the width L1 of the connection part 215. If thedifference between the width L2 of the rear end 211A of the dischargepart 211 and the width L1 of the connection part 215 is greater than100% the width L1 of the connection part 215, the sectional area of thedischarge part 211 is sharply increased with the result that it is notpossible to guide air flowing into the discharge port 211. On the otherhand, if the difference between the width L2 of the rear end 211A of thedischarge part 211 and the width L1 of the connection part 215 is lessthan 50% the width L1 of the connection part 215, the sectional area ofthe discharge part 211 is gently increased with the result that it isnot possible to reduce the flow speed of the air discharged from thedischarge part 211.

The difference between the width L2 of the rear end 211A of thedischarge part 211 and the width L1 of the connection part 215 is avalue obtained by subtracting the width L1 of the connection part 215from the width L2 of the rear end 211A of the discharge part 211.Additionally, the width L1 of the connection part 215 is equal to thewidth of the front end of the discharge part 211.

Additionally, the rear end 211A of the discharge part 211 may be locatedat the upper region of the case. Since the flow speed of the airdischarged from the discharge part 211 is higher than that of the airintroduced into the discharge part 211, noise is increased in thedischarge part 211.

In a case in which the rear end 211A of the discharge part 211 islocated at the upper region of the case and the front F of the blowerapparatus 200 in the axial direction of the blower apparatus 200 isaligned with a direction of gravity, therefore, the air is dischargedfrom the discharge part 211 toward the upper side of the case.

The case has a predetermined height and, therefore, the discharge part211 is installed at the predetermined height from the ground. As aresult, it is possible to reduce noise that people may hear in ear.

More particularly, in a case in which the height of the rear end 211A ofthe discharge part 211 (which means the height from the ground) isdesigned to be equal to or greater than the average height of people, itis possible to further reduce noise of the air discharged from thedischarge part 211.

The sectional holes may be located under the discharge part 211. Sincethe sectional holes are disposed at three sides of the case, the flowspeed of the air suctioned through the sectional holes is reduced.Consequently, noise is low even when the sectional holes are disposedadjacent to ears of people.

The suction part 213 guides air suctioned from the front F to the rear Rof the blower apparatus 200 in the axial direction of the blowerapparatus 200 by the blower fan 300. That is, the suction part 213increases the flow speed of the air suctioned by the blower fan 300.

The suction part 213 defines the inlet port 212 of the orifice 210. Morespecifically, the suction part 213 may have a shape having the inletport 212 defined therein. For example, the suction part 213 may beformed in a shape in which the front F and the rear R of the blowerapparatus 200 in the axial direction of the blower apparatus 200 areopened and the suction part 213 surrounds the blower fan 300 in adirection perpendicular to the axial direction of the blower apparatus200. That is, the suction part 213 is formed approximately in acylindrical shape.

The suction part 213 is located at the front F of the blower fan 300 inthe axial direction of the blower apparatus 200. That is, the suctionpart 213 is located opposite to the discharge part 211 via the blowerfan 300.

The center of the suction part 213 may be aligned with the shaft of theblower fan 300.

The sectional area of the suction part 213 is gradually increased fromthe front F to the rear R of the blower apparatus 200 in the axialdirection of the blower apparatus 200. Additionally, the width of thesuction part 213 is also gradually increased.

Consequently, the flow speed of the air suctioned by the blower fan 300is increased.

The sectional area means the area of a plane perpendicular to the axialdirection of the blower apparatus 200.

More specifically, the rear end of the suction part 213 is connected tothe connection part 215 and the front end 213A of the suction part 213is located more adjacent to the front F of the blower apparatus 200 inthe axial direction of the blower apparatus 200 than the front end ofthe blower fan 300.

Consequently, it is possible to sufficiently increase the flow speed ofthe air suctioned into the blower fan 300.

The front end 213A of the suction part 213 means an end of the suctionpart 213 located at the front F of the blower apparatus 200 in the axialdirection of the blower apparatus 200 and the rear end of the suctionpart 213 means an end of the suction part 213 located at the rear R ofthe blower apparatus 200 in the axial direction of the blower apparatus200.

That is, the suction part 213 may have a uniform height. The height ofthe suction part 213 means the distance from the front end 213A of thesuction part 213 to the rear end of the suction part 213.

The axial section of the suction part 213 may have a linear or curvedshape. The axial section means the sectional area of a plane parallel tothe axial direction of the blower apparatus 200.

The connection part 215 connects the suction part 213 and the dischargepart 211 to each other. Alternatively, the connection part 215 may be anideal part meaning a connection point between the rear end of thesuction part 213 and the front end of the discharge part 211.

The connection part 215 guides air suctioned from the front F to therear R of the blower apparatus 200 in the axial direction of the blowerapparatus 200 by the blower fan 300.

More specifically, the connection part 215 may be formed in a shape inwhich the front F and the rear R of the blower apparatus 200 in theaxial direction of the blower apparatus 200 are opened and theconnection part 215 surrounds the blower fan 300 in a directionperpendicular to the axial direction of the blower apparatus 200. Thatis, the connection part 215 is formed approximately in a cylindricalshape.

The blower fan 300 is disposed in the connection part 215. Theconnection part 215 defines an air flow channel around the blower fan300.

The center of the connection part 215 may be aligned with the shaft ofthe blower fan 300.

The sectional area of the connection part 215 may be sufficient suchthat the blower fan 300 is disposed in the connection part 215 and theblower fan 300 is rotatable.

More specifically, the front end of the connection part 215 is connectedto the rear end of the suction part 213 and the rear end of theconnection part 215 is connected to the front end of the discharge part211.

Ribs 217 to increase rigidity of the orifice 210 may be disposed at theouter circumference of the orifice 210.

The ribs 217 are disposed around the orifice 210 in a radial manner toincrease rigidity of the orifice 210.

FIG. 6 is a perspective view showing a blower fan according to anembodiment. FIG. 7 is a plan view of the blower fan shown in FIG. 6.FIG. 8 is a side view of the blower fan shown in FIG. 6. Otherembodiments and configurations may also be provided.

Referring to FIGS. 6 to 8, the blower fan 300 according to theembodiment includes a hub 310 fixed to a rotary shaft 231, a main rib320 disposed to surround the hub 310 while being spaced apart from theouter circumference of the hub 310, a plurality of auxiliary ribs 330connected to the outer circumference of the main rib 320 to connect thehub 310 and the main rib 320 to each other, and a plurality of blades340 coupled to the outer circumference of the hub 310 to generate an airstream (or air flow) during rotation the blower fan 300.

The hub 310 is fixed to the rotary shaft 231. More specifically, the hub310 may be formed in a cylindrical shape surrounding the rotary shaft231.

More specifically, the hub 310 may be disposed at a plane perpendicularto the rotary shaft 231 to surround the rotary shaft 231 in acylindrical shape.

The auxiliary rib 330 is connected to the outer circumference of the hub310. A space in which the rotary shaft 231 is located is defined in thehub 310.

The hub 310 is rotated according to rotation of the rotary shaft 231 totransmit rotational force to the blades 340 and the auxiliary rib 330.

The main rib 320 is disposed to surround the hub 310 while being spacedapart from the outer circumference of the hub 310.

More specifically, the main rib 320 may be disposed at a planeperpendicular to the rotary shaft 231 to surround the hub 310 whilebeing spaced apart from the outer circumference of the hub 310

The main rib 320 may be formed in various shapes so long as the main rib320 is disposed at a plane perpendicular to the rotary shaft 231 tosurround the hub 310.

More specifically, the main rib 320 may be disposed at a planeperpendicular to the rotary shaft 231 such that the main rib 320 issymmetric with respect to the rotary shaft 231.

More specifically, the main rib 320 may be on a plane perpendicular tothe rotary shaft 231, having a cylindrical shape with the rotary shaft231 as its axis.

The main rib 320 may include a main rib inner circumference 321, towhich the auxiliary rib 330 is coupled, and a main rib outercircumference 323, to which the blades 340 are coupled.

When the hub 310 is rotated to transmit rotational force to the blades340, and the main rib 320 eliminates stress concentrated between theblades 340 and the hub 310.

The blades 340 are connected to the main rib outer circumference 323 ofthe main rib 320 to generate an air stream directed from the front F tothe rear R of the blower fan 300 in the axial direction of the blowerfan 300.

The blades 340 may be formed in various shapes so long as the blades 340generate an air stream (or air flow) directed from the front F to therear R of the blower fan 300 in the axial direction of the blower fan300 during rotation.

For example, the blades 340 may be disposed at a plane perpendicular tothe rotary shaft 231 such that the blades 340 are gradually inclinedtoward the rear R of the blower fan 300 in the axial direction of theblower fan 300 from the front of the blades 340 in the rotationaldirection of the blades 340 to the rear of the blades 340 in therotational direction of the blades 340.

As shown in FIG. 7, each blade 340 may include a blade inner edge 349adjacent to the hub 310, a blade outer edge 343 opposite to the bladeinner edge 349, a blade front edge 345 defining the front outline of theblade 340 in the rotational direction of the blade 340, and a blade rearedge 347 defining the rear outline of the blade 340 in the rotationaldirection of the blade 340. That is, the border of each blade 340 isdefined by the blade inner edge 349, the blade outer edge 343, the bladefront edge 345, and the blade rear edge 347.

The blade inner edge 349 of each blade 340 may be coupled to the outercircumference of the main rib 320.

The blade front edge 345 may be positioned forward than the blade rearedge 347.

The blade front edge 345 may be located more adjacent to the front F ofthe blower fan 300 in the axial direction of the blower fan 300 than theblade rear edge 347. When the blades 340 are rotated in the rotationaldirection of the blades 340, therefore, the blade front edge 345generates an air stream directed from the front F to the rear R of theblower fan 300 in the axial direction of the blower fan 300 since theblade front edge 345 is located more adjacent to the front F of theblower fan 300 in the axial direction of the blower fan 300 than theblade rear edge 347.

The blade front edge 345 may be positioned forward than the blade rearedge 347 in the axial direction of the blower fan.

Each blade 340 may be on a plane perpendicular to the rotary shaft 231such that the blade 340 is shaped, from its front tip in the rotationaldirection of the blower fan 300 to its rear end, to be curved toward therear of the blower fan.

Of course, in order to smoothly achieve the air stream (or air flow)generated from the front F to the rear R of the blower fan 300 in theaxial direction of the blower fan 300, the blades 340 may be roundedwhile being on a plane perpendicular to the rotary shaft 231 such thatthe blades 340 are gradually inclined toward the rear R of the blowerfan 300 in the axial direction of the blower fan 300 from the front ofthe blades 340 in the rotational direction of the blades 340 to the rearof the blades 340 in the rotational direction of the blades 340.

The blade rear edge 347 may have a waveform shape 348. Morespecifically, the blade rear edge 347 may be convex and concave in theforward and backward directions of the blades 340 in the rotationaldirection of the blades 340. Alternatively, the blade rear edge 347 maybe convex and concave from the front F to the rear R of the blower fan300 in the axial direction of the blower fan 300.

An air stream (or air flow) generated along a positive pressure plane ofeach blade 340 (a plane at the rear R of the blower fan 300 in the axialdirection of the blower fan 300) generates noise when leaving the bladerear edge 347. In a case in which the blade rear edge 347 has a waveformshape 348, noise is reduced due to interference between air streamsleaving the blade rear edge 347.

A radius R1 of the main rib 30 may be 20% to 30% of a radius R2 of theblade outer edge 343. As shown in FIG. 7, the radius means a radiushaving the rotary shaft 231 as the center at a plane perpendicular tothe rotary shaft 231. In particular, the radius R2 of the blade outeredge 343 is the largest in radii of the entire edges of the blades.

If the radius R1 of the main rib 30 is less than 20% of the radius R2 ofthe blade outer edge 343, the contact area between the blade outer edge343 and the outer circumference 323 of the main rib 320 is decreasedwith the result that stress applied to the blade inner edge 349 isincreased during rotation of the blades 340. On the other hand, if theradius R1 of the main rib 30 is greater than 30% of the radius R2 of theblade outer edge 343, stress applied to the blade inner edge 349 isdecreased during rotation of the blades 340. However, the radius of themain rib 320 is increased with the result that manufacturing cost of themain rib 320 is increased. Additionally, the area of the main rib 320 isincreased with the result that a flow rate of the blower fan 300 isdecreased.

The auxiliary rib 330 connects between the hub 310 and the main rib 320to eliminate stress concentrated at the outer circumference of the hub310 during rotation of the blades 340. Additionally, the auxiliary rib330 generates an air stream (or air flow) during rotation of the blades340.

The auxiliary rib 330 is coupled to the outer circumference of the hub310 such that the auxiliary rib 330 is connected between the hub 310 andthe main rib 320.

The plurality of auxiliary ribs 330 are arranged around the hub 320.

The auxiliary rib 330 generates an air stream (or air flow) to onedirection. For example, the auxiliary rib 330 may be rotated by the hub310 to generate an air stream (or air flow) during the rotation of theblower fan in the same direction with the plurality of blades 340. Theauxiliary rib 330 generates an air stream (or air flow) from the front Fto the rear R of the blower fan 300 in the axial direction of the blowerfan 300.

More specifically, an inner edge of the auxiliary rib 330 is connectedto the outer circumference of the hub 310 and an outer edge of theauxiliary rib 330 is connected to the inner circumference 321 of themain rib 320.

The auxiliary rib 330 may be on a plane perpendicular to the rotaryshaft 231 such that the auxiliary rib 330 is disposed about the rotaryshaft in a radial manner.

The plurality of auxiliary ribs 330 are shaped, from its front tip inthe rotational direction of the blower fan 300 to its rear end, to becurved toward a rear of the blower fan 300.

A plurality of auxiliary ribs 330 may be provided. A plurality ofauxiliary ribs may be arranged apart from each other. The number of theauxiliary ribs 330 is not particularly restricted. For example, thenumber of the auxiliary ribs 330 may correspond to that of the blades340.

The auxiliary rib 330 may include an inner edge adjacent to the hub 310,an outer edge opposite to the inner edge, an auxiliary rib front edge335 defining the front outline of the auxiliary rib 330 in therotational direction of the blade 340, and an auxiliary rib rear edge337 defining the rear outline of the auxiliary rib 330 in the rotationaldirection of the blade 340. That is, the border of the auxiliary rib 330is defined by the inner edge, the outer edge, the auxiliary rib frontedge 335, and the auxiliary rib rear edge 337.

The auxiliary rib 330 may have a shape to generate an air stream (or airflow) directed from the front F to the rear R of the blower fan 300 inthe axial direction of the blower fan 300 during rotation. Morespecifically, the auxiliary rib 330 may be disposed at a planeperpendicular to the rotary shaft 231 such that the auxiliary rib 330 isgradually inclined toward the rear R of the blower fan 300 in the axialdirection of the blower fan 300 from the front of the blades 340 in therotational direction of the blades 340 to the rear of the blades 340 inthe rotational direction of the blades 340.

More specifically, the auxiliary rib front edge 335 may be located moreadjacent to the front F of the blower fan 300 in the axial direction ofthe blower fan 300 than the auxiliary rib rear edge 337. The auxiliaryrib front edge 335 is positioned forward than the auxiliary rib rearedge 337 in the axial direction of the blower fan.

When the auxiliary rib 330 are rotated in the rotational direction ofthe auxiliary rib 330, therefore, the auxiliary rib 330 generates an airstream directed from the front F to the rear R of the blower fan 300 inthe axial direction of the blower fan 300 due to the shape of theauxiliary rib 330.

Of course, in order to smoothly achieve the air stream generated fromthe front F to the rear R of the blower fan 300 in the axial directionof the blower fan 300, the auxiliary rib 330 may be rounded while beingdisposed at a plane perpendicular to the rotary shaft 231 such that theauxiliary rib 330 is gradually inclined toward the rear R of the blowerfan 300 in the axial direction of the blower fan 300 from the front ofthe auxiliary rib 330 in the rotational direction of the auxiliary rib330 to the rear of the auxiliary rib 330 in the rotational direction ofthe auxiliary rib 330.

A thickness of the plurality of auxiliary ribs 330 increases graduallyfrom the main rib 320 to the hub 310.

The auxiliary rib rear edge 337 may have a waveform shape 337-1. Morespecifically, the auxiliary rib rear edge 337 may be convex and concavein the forward and backward directions of the auxiliary rib 330 in therotational direction of the auxiliary rib 330. Alternatively, theauxiliary rib rear edge 337 may be convex and concave from the front Fto the rear R of the blower fan 300 in the axial direction of the blowerfan 300.

An air stream generated along a positive pressure plane of auxiliary rib330 (a plane at the rear R of the blower fan 300 in the axial directionof the blower fan 300) generates noise when leaving the auxiliary ribrear edge 337. In a case in which the auxiliary rib rear edge 337 has awaveform shape, air streams may be slightly delayed when leaving theauxiliary rib rear edge 337 and, therefore, noise is reduced due tointerference between the air streams.

The auxiliary rib rear edge 337 adjacent to the main rib 320 and theblade rear edge 347 adjacent to the main rib 320 may be adjacent to eachother on a circumference (for example, the main rib 320) having therotary shaft as the center.

FIG. 9A is a view illustrating the flow of air generated by a blowerfan. FIG. 9B is view illustrating the flow of air generated by theblower fan according to the embodiment. Other embodiments andconfigurations may also be provided.

Referring first to FIG. 9A, the blower fan is configured to have astructure in which a main plate extends from a hub in a radial directionof the hub and blades are coupled to the outer circumference of the mainplate.

More specifically, the main plate is disposed at a plane perpendicularto the rotary shaft 231 such that the main plate extends outward fromthe outer circumference of the hub to surround the outer circumferenceof the hub.

When the blades are rotated, an air stream (or air flow) is generatedfrom the front F to the rear R of the blower fan in an axial directionof the blower fan by the blades.

At this time, a space defined between the main plate and the hub isclosed such that the air stream cannot pass through the space. As aresult, the air stream generated by rotation of the blades forms an eddyon the main plate at the rear R in an axial direction of the blower fan.

The eddy reduces efficiency of the blower fan and increased noise.

Referring now to FIG. 9B, the blower fan 300 according to the embodimentis configured such that the auxiliary rib 330 is connected between thehub 310 and the main rib 320 and the auxiliary rib 330 is formed in theshape of a blade. Consequently, stress generated during rotation of theblades 340 is distributed to the main rib 320 and the auxiliary rib 330.During rotation of the blades 340, the auxiliary rib 330 is also rotatedto generate an air stream.

Consequently, an air stream flowing from the front F to the rear R ofthe blower fan 300 in the axial direction of the blower fan 300 isgenerated in a space defined between the hub 310 and the main rib 320.When an air stream flowing from the front F to the rear R of the blowerfan 300 in the axial direction of the blower fan 300 is generated in thespace defined between the hub 310 and the main rib 320, efficiency ofthe blower fan is improved and an eddy generated at the hub 310 at therear R of the blower fan 300 in the axial direction of the blower fan300 is reduced, thereby reducing noise.

FIG. 10 is a plan view showing a blower fan according to anotherembodiment. Other embodiments and configurations may also be provided.

Referring to FIG. 10, a blower fan 300A according to this embodiment isdifferent from the blower fan according to the embodiment shown in FIG.7 in that the position of the auxiliary rib 330 is changed.

More specifically, the auxiliary rib rear edge 337 adjacent to the mainrib 320 and the blade rear edge 347 adjacent to the main rib 320 may bealternately arranged on a circumference (for example, the main rib 320)having the rotary shaft as the center.

More specifically, a connection of the auxiliary rib rear edge 337 tothe main rib 320 and a connection of the blade rear edge 347 to the mainrib 320 may alternate along the circumference of the main rib 320.

A connection of the auxiliary rib rear edge 337 to the main rib 320 anda connection of the blade rear edge 347 to the main rib 320 correspondto each other on an inner and outer surface of the main rib 320.

When an air stream leaves the blade rear edge 347 and the auxiliary ribrear edge 337, noise is generated. In the above structure in which theauxiliary rib rear edge 337 adjacent to the main rib 320 and the bladerear edge 347 adjacent to the main rib 320 are alternately arranged onthe circumference (having the rotary shaft as the center), noise isreduced due to interference between air streams leaving the blade rearedge 347 and the auxiliary rib rear edge 337.

As is apparent from the above description, the blower fan and the airconditioner having the same have one or more of the following effects.

In the blower fan and the air conditioner having the same according tothe embodiment, the auxiliary rib is connected between the hub and themain rib and the auxiliary rib is formed in the shape of a blade.Consequently, stress generated during rotation of the blades isdistributed to the main rib and the auxiliary rib. During rotation ofthe blades, the auxiliary rib is also rotated to generate an air stream,thereby increasing a flow rate of air blown by the blower fan.

In addition, an air stream flowing from the front F to the rear R of theblower fan in the axial direction of the blower fan is generated in thespace defined between the hub and the main rib, thereby improvingefficiency of the blower fan. Furthermore, an eddy generated at the hubat the rear of the blower fan in the axial direction of the blower fanis reduced, thereby reducing noise.

As the flow rate of air blown by the blower fan is increased, heatexchange performance of the heat exchanger is improved, therebyimproving efficiency of the air conditioner.

It is an object of embodiments to provide a blower fan exhibiting a highflow rate and low noise and an air conditioner having the same.

In accordance with an aspect of an embodiment, the above and otherobjects can be accomplished by the provision of a blower fan including ahub fixed to a rotary shaft, a main rib disposed to surround the hubwhile being spaced apart from an outer circumference of the hub, anauxiliary rib connected between the hub and the main rib, and aplurality of blades coupled to an outer circumference of the main rib togenerate an air stream during rotation thereof, wherein the auxiliaryrib is rotated by the hub to generate an air stream to same directionwith the plurality of blades.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A blower fan comprising: a hub attached to arotary shaft; a main rib to surround the hub and be spaced apart from acircumference of the hub; a plurality of auxiliary ribs to connect themain rib to the hub; and a plurality of blades connected to acircumference of the main rib, the plurality of blades to provide an airflow during rotation of the blower fan, wherein the plurality ofauxiliary ribs to provide an air flow, in a same direction as theplurality of clades, during rotation of the blower fan.
 2. The blowerfan according to claim 1, wherein an inner edge of the plurality ofauxiliary ribs is connected to an outer circumference of the hub, and anouter edge of the plurality of auxiliary ribs is connected to an innercircumference of the main rib, and the plurality of auxiliary ribs areon a plane perpendicular to the rotary shaft such that the plurality ofauxiliary ribs are provided in a radial manner about the rotary shaft.3. The blower fan according to claim 1, wherein the plurality ofauxiliary ribs are shaped, from a front tip in a rotational direction ofthe blower fan to a rear end, to be curved toward a rear of the blowerfan.
 4. The blower fan according to claim 3, wherein the plurality ofauxiliary ribs includes: an auxiliary rib front edge to define a frontoutline of the auxiliary rib in a rotational direction of the blades;and an auxiliary rib rear edge to define a rear outline of the auxiliaryrib in the rotational direction of the blades, and wherein the auxiliaryrib front edge is provided forward than the auxiliary rib rear edge inan axial direction of the blower fan.
 5. The blower fan according toclaim 4, wherein a total number of the plurality of auxiliary ribscorresponds to a total number of the plurality of blades.
 6. The blowerfan according to claim 4, wherein the auxiliary rib rear edge has awaveform shape.
 7. The blower fan according to claim 4, wherein the mainrib is on a plane perpendicular to the rotary shaft, and the main ribhas a cylindrical shape with the rotary shaft as its axis.
 8. The blowerfan according to claim 7, wherein a radius of the main rib is 20% to 30%of a radius of rotation of the plurality of blades.
 9. The blower fanaccording to claim 7, wherein each blade includes: a blade front edge todefine a front outline of the blade in the rotational direction of theblade; and a blade rear edge to define a rear outline of the blade inthe rotational direction of the blade, and wherein the blade front edgeis provided forward than the blade rear edge in the axial direction ofthe blower fan.
 10. The blower fan according to claim 9, wherein aninner edge of each blade is connected to an outer circumference of themain rib, and a connection of the auxiliary rib rear edge to the mainrib and a connection of the blade rear edge to the main rib alternatealong the circumference of the main rib.
 11. The blower fan according toclaim 10, wherein the blade rear edge has a waveform shape.
 12. An airconditioner comprising: a case; a compressor to compress a refrigerant;a heat exchange, disposed in the case, to perform heat exchange betweenair and the refrigerant; and a blower fan to blow the air, wherein theblower fan includes: a hub attached to a rotary shaft; a main rib tosurround the hub and be spaced apart from a circumference of the hub; aplurality of auxiliary ribs to connect the main rib to the hub; and aplurality of blades to connect to a circumference of the main rib, theplurality of blades to provide an air flow during rotation of the blowerfan, wherein the plurality of auxiliary ribs to provide an air flow, ina same direction as a plurality of blades, during rotation of the blowerfan.
 13. The air conditioner according to claim 12, further comprisingan orifice to guide the air blown by the blower fan.
 14. The airconditioner according to claim 13, wherein an inner edge of theplurality of auxiliary ribs is connected to an outer circumference ofthe hub, and an outer edge of the plurality of auxiliary ribs isconnected to an inner circumference of the main rib, and the pluralityof auxiliary ribs are on a plane perpendicular to the rotary shaft suchthat the plurality of auxiliary ribs are provided in a radial mannerabout the rotary shaft.
 15. The air conditioner according to claim 14,wherein the auxiliary rib is inclined from the plane perpendicular tothe rotary shaft.
 16. The air conditioner according to claim 15, whereinthe plurality of auxiliary ribs includes: an auxiliary rib front edge todefine a front outline of the auxiliary rib in a rotational direction ofthe blades; and an auxiliary rib rear edge to define a rear outline ofthe auxiliary rib in the rotational direction of the blades, and whereinthe auxiliary rib front edge is provided forward than the auxiliary ribrear edge in an axial direction of the blower fan.
 17. The airconditioner according to claim 16, wherein the main rib is on a planeperpendicular to the rotary shaft, and the main rib has a cylindricalshape with the rotary shaft as its axis.
 18. The air conditioneraccording to claim 17, wherein a radius of the main rib is 20% to 30% ofa radius of rotation of the plurality of blades.
 19. The air conditioneraccording to claim 18, wherein an inner edge of each blade is connectedto an outer circumference of the main rib, and a connection of theauxiliary rib rear edge to the main rib and a connection of the bladerear edge to the main rib alternate along the circumference of the mainrib.
 20. The air conditioner according to claim 12, wherein a thicknessof the auxiliary rib increases gradually from the main rib to the hub.